diff --git a/swash/config.ini b/swash/config.ini
index 560cfa6..657a41b 100644
--- a/swash/config.ini
+++ b/swash/config.ini
@@ -12,6 +12,7 @@ out=out_data
 out_nb=out_data_nb
 
 [swash]
+nb=True
 input=sws/INPUT.sws
 path=/opt/swash
 out=out_sws
diff --git a/swash/processing/swash.py b/swash/processing/swash.py
index d73cce8..c86a769 100644
--- a/swash/processing/swash.py
+++ b/swash/processing/swash.py
@@ -30,8 +30,12 @@ with tempfile.TemporaryDirectory(prefix="swash_", dir=".") as tmp_raw:
 
     log.info(f"Copying files to '{tmpdir}'")
     shutil.copy2(inp, tmpdir)
+    if config.getboolean("swash", "nb", fallback=False):
+        path = pathlib.Path(config.get("data", "out_nb"))
+    else:
+        path = pathlib.Path(config.get("data", "out"))
     shutil.copytree(
-        pathlib.Path(config.get("data", "out")), tmpdir, dirs_exist_ok=True
+        path, tmpdir, dirs_exist_ok=True
     )
 
     if config.has_option("swash", "mpi"):